In the first part of the talk, the AMS01 experiment and the 1998
instrumental flight will be described, the results will be summarized
and their interpretation illustrated. Next, the main features of the new
AMS02 spectrometer will be reviewed and put in perspective with the
AMS01 instrument, and the Physics program of the experiment will be
outlined. 
The second part will be devoted to a detailed presentation of the RICH
counter: The design requirements and the choices made for the
instrumentation will be reviewed. The Physics case for particle
(isotope) identification will be discussed in this context. The chosen
configuration, radiator(s), photodetectors, and the expected
performances will be described and discussed, and the current status of
the project and of the prototype testing will be widely illustrated,
before the summary and the conclusion will be given.